First things first its python and qt. To me it feels quite responsive. I also have no idea what "modern" means in this context unless you mean flat with few buttons or options. Calibre can be styled by choosing a qt5 style for your system. If your default is ugly you ought to change it. Such styles can be chosen in your gui configuration menu or via qt5ct at least under linux.

This is what it looks like for me. http://imgur.com/a/px8zF

That said I don't want to start up a whole app just to open a book I usually just open books via a script that wraps calibredb a cli interface to calibre's ebook library. If more than one result is available in response to a query it shows them via rofi. https://davedavenport.github.io/rofi/

It also remembers the last n books that have been opened whether they have been opened in the gui, a script, or otherwise and when called without arguments it returns the list of recent reads which can be selected via rofi. Since I often return to the same several books repeatedly on multiple sessions this is a more pleasant way to access my books.

My script is a bunch of not so awsome shell script. If you want to improve something a better cli experience out of the box for calibre would be nice.

Calibre feels like a set of tools which can be accessed by a UI, its not really intuitively organized. There's not much of a sense of a hierarchy of concerns for instance. Still, credit to the maintainer, it's an amazing piece of work.

I've used it for years and love its features but yeah the UI and processing always felt heavy like a java app but as someone else noted it's not java - it's python so I suspect the laggy of slowness in the UI might be a side effect of python's single threaded / GIL performance issues. Python can be fast, especially for scientific work but in my experience - I get annoyed by python apps more than other interpreted languages such as Ruby as it often seems to peg a single core to 100% whenever I'm waiting for something to finish processing - again I'm sure it's the way things are written more than the language itself as such but it seems it makes it hard to write python applications that make efficient use of modern multi core CPUs. (I host a lot of Python, Ruby and web apps written in various other languages).

For what it's worth, there isn't a single line of Java in the source code.

https://github.com/kovidgoyal/calibre

Hey just be glad it's not another one of those even clunkier nodejs "desktop" apps

To be honest though, calibre just works for me. Sure it's not a super optimized c++ project but there's so many things it can do. See I just need to transfer ebooks to my kindle, and it does it perfectly every time.

> Perhaps this is a good side project for me to delve into ;)

By all means, please do. There are no alternatives out there to calibre. I think its an excellent app once you get used to it, but competition is healthy.

I don't find it heavy, just that the UI is not pleasant. From the icon, to the splash screen, to the many extraneous menu items and buttons. I find it painful to use, but there doesnt seem to be a good alternative. I guess that means I should create one.

Calibre is written in Python

Much as I love pyGTK, apps written in it feel pretty chunky :/

Here's looking at you, Mint Menu

(not nearly as bad as Electron though)

I disagree, while Electron apps have trade offs, I never experience the experience of clunkiness I find with Calibre.

Try resizing a window in any Electron app. Bonus points if you have display scaling enabled.

Works fine. That's not the issue with electron (for me at least), it's battery life/power consumption.

On every machine I've used any Electron app on, there are large gray areas that flash and lag behind the mouse cursor when resizing (it's especially noticeable on Slack). On hidpi displays, half the time there are 1px black lines remaining on the right and bottom sides (probably due to poor rounding). Compare that to native apps like Sublime or Windows Explorer.

Just tested on both a 4k 13" Windows Display and a 2K 15" Mac Display - yes I see what you mean. That is pretty bad, though I've never noticed that before.

its qt

> I suspect this is due to the program being written in Java.

Nope, it's Python.